摘要AIM: To reverse the multidrug resistance (MDR) by RNA interference (RNAi)-mediated MDR1 suppression in hepatoma cells.METHODS: For reversing MDR by RNAi technology, two different short hairpin RNAs (shRNAs) were designed and constructed into pGenSil-1 plasmid, respectively. They were then transfected into a highly adriamycin-resistant HepG2 hepatoma cell line (HepG2/ADM). The RNAi effect on MDR was evaluated by real-time PCR, cell cytotoxicity assay and rhodamine 123 (Rh123) efflux assy.RESULTS: The stably-transfected clones showed various degrees of reversal of MDR phenotype. Surprisingly, the MDR phenotype was completely reversed in two transfected clones.CONCLUSION: MDR can be reversed by the shRNAmediated MDRI suppression in HepG2/ADM cells, which provides a valuable clue to make multidrug-resistant hepatoma cells sensitive to anti-cancer drugs.